"Not all S Units are created equal. Depending upon the radio and the S Unit (S0 to S9), the value of an S Unit, as measured in dBs, changes quite a bit. It can range from less than 1 dB to almost 10 dB."

Standardisation is the English spelling of Standardization, which is the American spelling. Note that the IARU is the International Amateur Radio Union and not the ARRL.

S-units on the K3? I understand it is 5 to 6 dB per S-unit.

-93 dBm on 144 MHz and above vs -73 dBm below 144 MHz: I imagine this is so that S-1 remains near the atmospheric noise level; so that we don't need to give reports such as "you are 6 dB below S-1, OM."

Standards change and improve over time. The NIST definition of the VOLT has changed several times in the past 40 years. The NIST definition of the unit of length the METER has changed from a physical artifact to an electronically derived measurement.

As noted the Flex is calibrated for 6 dB S-units and the Elecraft K3 for 5-6 dB S-units. These are the two highest performance amateur receivers, according to the Sherwood Engineering reports. These two manufacturers are evidence that the 6 dB/S-unit spec is not totally ignored.

Your assertions that standardisation is mispelled, that there is a 30/144 MHz descrepancy, and that the S-unit is totally ignored have been refuted. Have you other assertions to voice in your attempt to discredit the S-unit?

I never said "standardisation" was misspelled. Its spelling just isn't standardized.

The IARU "technical recommendation" is for Region One which includes only "Europe, Africa, Middle East and Northern Asia." I live in Region Two. My equipment was made in Region Two and Region Three (Japan).

That R-E-C-O-M-M-E-N-D-A-T-I-O-N was adopted in 1981. I remember reading about S-units being 6 (or sometimes 5) dB in the 1950s. The IARU, for God-Knows-What-Reason simply attempted to codify a long recognized but rarely realized goal.

I doubt that obscure 1981 IARU Region One recommendation amounts to a Hill of Beans. The internationally recognized "Hill of Beans" is defined as 1.5 Imperial Hogsheads.

"8.6.1 SIGNAL REPORTING ( Recommendation R.1; R.2)Although from the beginning of amateur radio signal reports have been essential, no formal standard forthe reports exists. But the "Readability, Strength, Tone" system with R,S and T values between 1 and 9 isin widespread use. Several handbooks gave and give in words indications how the values are to beunderstood.The readability and tone reports are in principle "subjective" but the strength report can be objective as asimple measurement of the received signal in voltage or power is possible. Such reports are in particularat the VHF and higher frequencies useful for more precise evaluation of propagation, antenna propertiesand receiver sensitivities.At the IARU Region 1 Conference in Hungary 1978 the need for a harmonised standard for the "S-meterscale" was expressed and a proposal was accepted for publication in society journals. The essentialrecommendation was 1 S-point is 6 dB . At the Brighton Conference in 1981 the recommendation wasformally adopted as a standard for amateur radio equipment manufacturers.At the 1990 Torremolinos conference an amendment was adopted which reconfirmed the -93 dBmreference level for frequencies above 144 MHz, but no statement was issued for the bands between 30and 144 MHz.Although not explicitly stated the implication of the recommendation is that on VHF and higher frequenciesthe S-meter will deviate on the thermal noise only ( S2 in 3 kHz bandwidth, S3 in 12 kHz bandwidth).Although the recommendation is not too complex it seems to be rather difficult to implement bycommercial manufacturers.Another matter is the Atone@ report. This is a subjective measure. It was important in the Aolddays@when rather primitive oscillators were used in the TX. Modern transmitters, even on the millimeterbands, have in most cases a very good oscillator, resulting in a Apure tone@ and a T9 report is generallygiven. On VHF and higher, however, the characteristics of the propgation medium can significantlyAmodulate@the signal ( doppler shift, spreading) and a T9 report is not possible. Definitions of tonereports below 9 are rather vague. At the Region 1 conference 1999 in Lillehammer a recommendation(R.2) has been accepted to use special letters for signal tone reports when the influence of thepropagation is detectable. Such reports can support propagation studies."

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